How patients are transforming multiple sclerosis care

Historically, people living with MS have had little agency in how they were diagnosed and treated. But new research and input from members of the community are helping neurologists reassess how they approach the disease.

This article was created in partnership with Destination Toronto.

For years, the conversation went the same way. A patient with multiple sclerosis (MS) would visit their neurologist for a routine checkup. Out came the little black bag, and the doctor would run through reflex hammer and strength tests. An MRI would show no new lesions; there’d be no indication of active relapse, which happens when inflammation damages a nerve’s protective coating, causing a sustained flare-up of symptoms. Clinical trials labelled this “no evidence of disease activity,” a marker of treatment success. The doctor would report that everything looked stable, and the patient was doing well.

Except the patient might not agree. Something felt off — their thinking had slowed, they’d say, and they were having trouble at work. A hike that used to be a breeze now wiped them out after a third of the distance, and their gait was off. But these were fuzzy symptoms, easy to ignore or to brush off as aging, fatigue or something entirely unrelated.

MS is a complex inflammatory condition that affects the brain, spinal cord and optic nerve. In some ways, it’s an unusually difficult disease to get a read on. It typically shows when people are in their twenties to forties, a period when their bodies have the capacity to mask early damage — something researchers call “neurologic reserve.” Most patients are diagnosed with relapsing-remitting MS, a form of the condition characterized by intermittent attacks of symptoms followed by periods of recovery. The standard tools of a neurologic exam were built to catch acute, obvious deficits: a bout of double vision or the sudden inability to hold a pen. They weren’t designed for the slow, cumulative decline that defines much of the disease, at least as reported by those living with it.

A shift in the interpretation of data

“Patients have been telling us for so long that, despite stable MRIs and no relapses, they were experiencing this gradual worsening,” says neurologist Dr. Jiwon Oh, director of the BARLO Multiple Sclerosis Centre at St. Michael’s Hospital in Toronto. “But our old-fashioned tools simply couldn’t detect that kind of progression.” However, that paradigm is starting to shift. The change is not the result of some new tool or innovation, but rather a new way of looking at existing data.

Dr. Jiwon Oh

About a decade ago, an international group of scientists led by Swiss neurologist Dr. Ludwig Kappos re-analyzed some clinical trial datasets, identifying two categories of patient deterioration: those who experienced worsening disability in conjunction with an active relapse, and those who didn’t. The latter is called progression independent of relapse activity, or PIRA, and the study found that it was neither a rare nor marginal phenomenon. Damage to the nervous system, the scientists concluded, doesn’t just happen during relapse attacks — it’s continuous and steady, causing ongoing cell loss even in the absence of obvious flare-ups. What’s more, it can be seen in patients with relapsing-remitting MS, even early in their disease, and is, in fact, the dominant driver of long-term disability.

The two forms of MS — relapsing-remitting and progressive, marked by a gradual worsening of symptoms — were long assumed to be two different diseases, with two diagnostic pathways. But this study, published in JAMA Neurology in 2020, provided evidence that progressive damage was happening in both. That finding fed a broader body of evidence, including research on whether shrinkage in regions of the spinal cord tracked with the “invisible” progression patients were reporting (it did) and if old lesions in the brain showed continued inflammation long after the initial damage (they did). The two forms of MS, it turns out, actually share the same underlying pathological mechanism; acute and chronic inflammation and neurodegeneration happen simultaneously, not sequentially or exclusively.

That evolving understanding of MS will be a central theme at MSToronto2026, the joint meeting of the Americas and European Committees for Treatment and Research in Multiple Sclerosis. Under the banner “Unifying Multiple Sclerosis,” more than 8,000 clinicians, researchers and industry representatives will gather in October to discuss many of the shifts already reshaping the field, including the move toward understanding MS as a single biological spectrum, rather than distinct relapsing and progressive diseases. But redefining what MS is only solves part of the problem. Before doctors can assess a patient’s disease course, they first have to be sure the MS diagnosis is right.

Confirming an MS diagnosis often means patients must wait — for referrals, for a second clinical attack, for a follow-up MRI to show a new lesion — while living with mounting uncertainty and anxiety. And even then, misdiagnosis is common. Between 10 and 20 percent of patients referred to MS specialty centres with a diagnosis turn out not to have the disease, and MRI — one of the main diagnostic tools — is central to the problem. On standard scans, a spot caused by MS could look nearly identical to one caused by a migraine, a small stroke, or structural changes some people are born with.

A powerful diagnostic tool

Dr. Daniel Ontaneda is a neurologist with the Cleveland Clinic’s Mellen Center and an expert on MS misdiagnosis. His research centres on something called the central vein sign, a diagnostic marker with a surprisingly old backstory. Scientists have known since the late 1800s that MS lesions develop around tiny veins in the brain. Inflammatory cells then leak out of the vessel and damage the surrounding tissue. But that pattern was invisible on standard imaging until recently, when higher-resolution MRI sequences became sharp enough to actually see the vein sitting at the centre of a lesion.

The central vein sign has turned out to be a powerful diagnostic asset. According to Ontaneda, 80 to 90 percent of lesions in confirmed MS patients show a central vein, while conditions that mimic MS on a standard scan rarely do. After a decade of work building consensus in the field, the central vein sign was formally written into the McDonald criteria, which are international guidelines for MS diagnosis, in 2024. The meeting that finalized those revisions marked another milestone: it was the first time patient representatives sat at the table as the criteria themselves were being rewritten.

“As doctors, we have contact with patients, but sometimes we put on our research or clinician hat,” says Ontaneda, who, along with Oh, was on the committee that revised the guidelines. “It’s important to have them in the room to have their perspective.” That emphasis on bringing patients into the conversation is on the agenda at MSToronto2026. On October 23, the conference is hosting a Patient Community Day, a free public event where people living with MS, their families and others affected by the disease can hear about the latest research, emerging treatments and approaches to managing the condition.

Diagnosing MS is a fraught process, Ontaneda explains, and improving the patient’s experience is one of the reasons the criteria are updated every five to seven years. In an ideal world, the clinician and researcher hopes all patients would get a diagnosis based on a single test — that’s already the reality for many who come through his clinic. A faster, more confident diagnosis means less time spent in limbo, and, crucially, earlier access to disease-modifying treatments, which is linked to better outcomes.

A global hub for MS research

Canada has one of the highest MS rates in the world — the disease affects 290 in 100,000 people here compared to three in 100,000 in China — a fact epidemiologists still can’t fully explain. More than 90,000 Canadians live with the disease, and 12 more are diagnosed every day. The good news is that Toronto is a global hub for MS research and care. The BARLO centre at St. Michael’s Hospital, part of Unity Health Toronto, is one of the world’s major centres and recently underwent a $42-million rebuild, tripling in size and expanding its interdisciplinary team that follows more than 12,000 patients.

The BARLO Multiple Sclerosis Centre at St. Michael’s Hospital in Toronto is one of the world’s leading hubs for MS treatment and research.

Those strengths will be on display at MSToronto2026, where the program will cover some of the biggest questions in MS research, including how to treat the slow progression that patients helped bring into focus. Early clinical trials are investigating cell therapies, including CAR T-cell therapy, while new data are expected on Bruton’s tyrosine kinase inhibitors, or BTK inhibitors, a class of drugs designed to reach some of the chronic inflammatory processes that existing treatments largely miss.

“The biggest unmet need in MS right now is treating that slow decline,” says Oh. Most of the existing disease-modifying drugs work by suppressing peripheral immune activity, preventing relapses and the formation of new lesions in the brain, and they work well. But the so-called “smouldering inflammation” — the chronic, low-grade activity tied to PIRA — happens inside the central nervous system and can’t be touched by the majority of these therapies. “MS isn’t just about relapses and attacks,” says Oh. “It’s about this slow progression and the impact on patients’ lived experience. If we can address that, we’re that much closer to an actual cure for the disease.”

MSToronto2026 runs from Oct. 21–23 at the Metro Toronto Convention Centre. Patient Community Day takes place Oct. 23 and is free and open to the public. To sign up or learn more about the event, visit the website.

Main image source: Keith Tanner, Unsplash; Photos courtesy of Unity Health Toronto